Make schedule_on_each_cpu as EXPORT_SYMBOL.
Signed-off-by: Ritesh Harjani <[email protected]>
---
kernel/workqueue.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index f148eacda55a..6f15e4afbf38 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -3309,6 +3309,7 @@ int schedule_on_each_cpu(work_func_t func)
free_percpu(works);
return 0;
}
+EXPORT_SYMBOL(schedule_on_each_cpu);
/**
* execute_in_process_context - reliably execute the routine with user context
--
2.31.1
While debugging a issue, we needed to stress test the percpu alloc/free
path. Hence added some tests in lib/percpu_test to stress test
percpu subsystem for allocation with different sizes.
This patch keeps the default behavior of insmod module same for default
test. But when given insmod with different option, it can run a
percpu_stressd daemon (percpu_test_num=2) which does a stress test
evey 10secs unless the module is unloaded.
We found this to be helpful in our testing, since with this we could
easily excercise percpu allo/free path. Hence cleaned this up for
inclusion in percpu_test module.
Logs
======
qemu-> sudo insmod /mnt/percpu_test.ko percpu_test_num=0
[ 334.362973] percpu_test: INIT, interval: 1000, max_shift: 13, run_tests: percpu_verify
[ 334.364946] TEST Starts: percpu_verify
[ 334.365601] TEST Completed: percpu_verify
insmod: ERROR: could not insert module /mnt/percpu_test.ko: Resource temporarily unavailable
qemu-> sudo insmod /mnt/percpu_test.ko percpu_test_num=1
[ 336.556464] percpu_test: INIT, interval: 1000, max_shift: 13, run_tests: percpu_stress
[ 336.558388] TEST Starts: percpu_stress
[ 336.560611] TEST Completed: percpu_stress
insmod: ERROR: could not insert module /mnt/percpu_test.ko: Resource temporarily unavailable
qemu-> sudo insmod /mnt/percpu_test.ko percpu_test_num=2
[ 339.164406] percpu_test: INIT, interval: 1000, max_shift: 13, run_tests: percpu_stressd
[ 339.165935] TEST Starts: percpu_stressd
[ 339.167033] TEST Completed: percpu_stressd
[ 339.167082] DAEMON: starts percpu_stressd
[ 339.168498] TEST Starts: percpu_stressd: iter (1)
[ 339.182530] TEST Completed: percpu_stressd: iter (1)
[ 349.341109] TEST Starts: percpu_stressd: iter (2)
[ 349.344447] TEST Completed: percpu_stressd: iter (2)
[ 359.580829] TEST Starts: percpu_stressd: iter (3)
[ 359.584315] TEST Completed: percpu_stressd: iter (3)
[ 369.820471] TEST Starts: percpu_stressd: iter (4)
[ 369.844402] TEST Completed: percpu_stressd: iter (4)
qemu-> sudo rmmod percpu_test
[ 375.001098] percpu_test: EXIT
[qemu][~]
Cc: Aneesh Kumar K.V <[email protected]>
Cc: Vaibhav Jain <[email protected]>
Signed-off-by: Ritesh Harjani <[email protected]>
---
lib/percpu_test.c | 240 ++++++++++++++++++++++++++++++++++++----------
1 file changed, 191 insertions(+), 49 deletions(-)
diff --git a/lib/percpu_test.c b/lib/percpu_test.c
index 4a3d70bbc1a0..944d54c57b4b 100644
--- a/lib/percpu_test.c
+++ b/lib/percpu_test.c
@@ -1,4 +1,7 @@
// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/workqueue.h>
+#include <linux/kthread.h>
+#include <linux/cpu.h>
#include <linux/module.h>
/* validate @native and @pcp counter values match @expected */
@@ -14,10 +17,25 @@
(long long)(expected), (long long)(expected)); \
} while (0)
-static DEFINE_PER_CPU(long, long_counter);
-static DEFINE_PER_CPU(unsigned long, ulong_counter);
+/* upto max alloc size tests for percpu var */
+static char __percpu *counters[1 << PAGE_SHIFT];
+static struct task_struct *percpu_stressd_thread;
-static int __init percpu_test_init(void)
+/* let's not trigger OOM */
+int percpu_alloc_max_size_shift = PAGE_SHIFT - 3;
+module_param(percpu_alloc_max_size_shift, int, 0644);
+MODULE_PARM_DESC(percpu_alloc_max_size_shift, "max size of allocation in stress test will be upto 1 << percpu_alloc_max_size_shift");
+
+static long percpu_stressd_interval = 1 * 10 * HZ;
+module_param(percpu_stressd_interval, long, 0644);
+MODULE_PARM_DESC(percpu_stressd_interval, "percpu_stressd internal");
+
+/* keep the default test same */
+static int percpu_test_num;
+module_param(percpu_test_num, int, 0644);
+MODULE_PARM_DESC(percpu_test_num, "Test number percpu_test_num");
+
+static int percpu_test_verify(void)
{
/*
* volatile prevents compiler from optimizing it uses, otherwise the
@@ -26,109 +44,233 @@ static int __init percpu_test_init(void)
volatile unsigned int ui_one = 1;
long l = 0;
unsigned long ul = 0;
+ long __percpu *long_counter = alloc_percpu(long);
+ unsigned long __percpu *ulong_counter = alloc_percpu(unsigned long);
- pr_info("percpu test start\n");
+ if (!long_counter || !ulong_counter)
+ goto out;
+
+ pr_debug("percpu_test: %s start cpu: %d\n", __func__, smp_processor_id());
preempt_disable();
l += -1;
- __this_cpu_add(long_counter, -1);
- CHECK(l, long_counter, -1);
+ __this_cpu_add(*long_counter, -1);
+ CHECK(l, *long_counter, -1);
l += 1;
- __this_cpu_add(long_counter, 1);
- CHECK(l, long_counter, 0);
+ __this_cpu_add(*long_counter, 1);
+ CHECK(l, *long_counter, 0);
ul = 0;
- __this_cpu_write(ulong_counter, 0);
+ __this_cpu_write(*ulong_counter, 0);
ul += 1UL;
- __this_cpu_add(ulong_counter, 1UL);
- CHECK(ul, ulong_counter, 1);
+ __this_cpu_add(*ulong_counter, 1UL);
+ CHECK(ul, *ulong_counter, 1);
ul += -1UL;
- __this_cpu_add(ulong_counter, -1UL);
- CHECK(ul, ulong_counter, 0);
+ __this_cpu_add(*ulong_counter, -1UL);
+ CHECK(ul, *ulong_counter, 0);
ul += -(unsigned long)1;
- __this_cpu_add(ulong_counter, -(unsigned long)1);
- CHECK(ul, ulong_counter, -1);
+ __this_cpu_add(*ulong_counter, -(unsigned long)1);
+ CHECK(ul, *ulong_counter, -1);
ul = 0;
- __this_cpu_write(ulong_counter, 0);
+ __this_cpu_write(*ulong_counter, 0);
ul -= 1;
- __this_cpu_dec(ulong_counter);
- CHECK(ul, ulong_counter, -1);
- CHECK(ul, ulong_counter, ULONG_MAX);
+ __this_cpu_dec(*ulong_counter);
+ CHECK(ul, *ulong_counter, -1);
+ CHECK(ul, *ulong_counter, ULONG_MAX);
l += -ui_one;
- __this_cpu_add(long_counter, -ui_one);
- CHECK(l, long_counter, 0xffffffff);
+ __this_cpu_add(*long_counter, -ui_one);
+ CHECK(l, *long_counter, 0xffffffff);
l += ui_one;
- __this_cpu_add(long_counter, ui_one);
- CHECK(l, long_counter, (long)0x100000000LL);
+ __this_cpu_add(*long_counter, ui_one);
+ CHECK(l, *long_counter, (long)0x100000000LL);
l = 0;
- __this_cpu_write(long_counter, 0);
+ __this_cpu_write(*long_counter, 0);
l -= ui_one;
- __this_cpu_sub(long_counter, ui_one);
- CHECK(l, long_counter, -1);
+ __this_cpu_sub(*long_counter, ui_one);
+ CHECK(l, *long_counter, -1);
l = 0;
- __this_cpu_write(long_counter, 0);
+ __this_cpu_write(*long_counter, 0);
l += ui_one;
- __this_cpu_add(long_counter, ui_one);
- CHECK(l, long_counter, 1);
+ __this_cpu_add(*long_counter, ui_one);
+ CHECK(l, *long_counter, 1);
l += -ui_one;
- __this_cpu_add(long_counter, -ui_one);
- CHECK(l, long_counter, (long)0x100000000LL);
+ __this_cpu_add(*long_counter, -ui_one);
+ CHECK(l, *long_counter, (long)0x100000000LL);
l = 0;
- __this_cpu_write(long_counter, 0);
+ __this_cpu_write(*long_counter, 0);
l -= ui_one;
- this_cpu_sub(long_counter, ui_one);
- CHECK(l, long_counter, -1);
- CHECK(l, long_counter, ULONG_MAX);
+ this_cpu_sub(*long_counter, ui_one);
+ CHECK(l, *long_counter, -1);
+ CHECK(l, *long_counter, ULONG_MAX);
ul = 0;
- __this_cpu_write(ulong_counter, 0);
+ __this_cpu_write(*ulong_counter, 0);
ul += ui_one;
- __this_cpu_add(ulong_counter, ui_one);
- CHECK(ul, ulong_counter, 1);
+ __this_cpu_add(*ulong_counter, ui_one);
+ CHECK(ul, *ulong_counter, 1);
ul = 0;
- __this_cpu_write(ulong_counter, 0);
+ __this_cpu_write(*ulong_counter, 0);
ul -= ui_one;
- __this_cpu_sub(ulong_counter, ui_one);
- CHECK(ul, ulong_counter, -1);
- CHECK(ul, ulong_counter, ULONG_MAX);
+ __this_cpu_sub(*ulong_counter, ui_one);
+ CHECK(ul, *ulong_counter, -1);
+ CHECK(ul, *ulong_counter, ULONG_MAX);
ul = 3;
- __this_cpu_write(ulong_counter, 3);
+ __this_cpu_write(*ulong_counter, 3);
- ul = this_cpu_sub_return(ulong_counter, ui_one);
- CHECK(ul, ulong_counter, 2);
+ ul = this_cpu_sub_return(*ulong_counter, ui_one);
+ CHECK(ul, *ulong_counter, 2);
- ul = __this_cpu_sub_return(ulong_counter, ui_one);
- CHECK(ul, ulong_counter, 1);
+ ul = __this_cpu_sub_return(*ulong_counter, ui_one);
+ CHECK(ul, *ulong_counter, 1);
preempt_enable();
- pr_info("percpu test done\n");
- return -EAGAIN; /* Fail will directly unload the module */
+out:
+ free_percpu(long_counter);
+ free_percpu(ulong_counter);
+ pr_debug("percpu_test: %s done cpu: %d\n", __func__, smp_processor_id());
+
+ /*
+ * Keep the default functionality same.
+ * Fail will directly unload this module.
+ */
+ return -EAGAIN;
+}
+
+void percpu_test_verify_work(struct work_struct *work)
+{
+ percpu_test_verify();
+}
+
+static int percpu_test_stress(void)
+{
+ int i;
+
+ for (i = 1; i < (1 << percpu_alloc_max_size_shift); i++) {
+ size_t size = i;
+
+ if (size > PCPU_MIN_ALLOC_SIZE)
+ break;
+ counters[i] = (char __percpu *)__alloc_percpu(size, __alignof__(char));
+ if (!counters[i])
+ break;
+ cond_resched();
+ }
+
+ schedule_on_each_cpu(percpu_test_verify_work);
+
+ for (i = 0; i < (1 << percpu_alloc_max_size_shift); i++) {
+ free_percpu(counters[i]);
+ cond_resched();
+ }
+ return -EAGAIN;
+}
+
+static int percpu_stressd(void *v)
+{
+ int iter = 0;
+
+ pr_info("DAEMON: starts %s\n", __func__);
+ do {
+ if (kthread_should_stop())
+ break;
+ iter++;
+ pr_info("TEST Starts: %s: iter (%d)\n", __func__, iter);
+ percpu_test_stress();
+ pr_info("TEST Completed: %s: iter (%d)\n", __func__, iter);
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(percpu_stressd_interval);
+ } while (1);
+
+ return 0;
+}
+
+static int percpu_test_stressd(void)
+{
+ percpu_stressd_thread = kthread_run(percpu_stressd, NULL, "percpu_stressd");
+ if (IS_ERR(percpu_stressd_thread))
+ percpu_stressd_thread = NULL;
+ return 0;
+}
+
+enum test_type {
+ PERCPU_VERIFY,
+ PERCPU_STRESS,
+ PERCPU_STRESSD,
+ NR_TESTS,
+};
+
+const char *test_names[NR_TESTS] = {
+ [PERCPU_VERIFY] = "percpu_verify",
+ [PERCPU_STRESS] = "percpu_stress",
+ [PERCPU_STRESSD] = "percpu_stressd",
+};
+
+static int __init percpu_test_init(void)
+{
+ int i, ret = 0;
+ typedef int (*percpu_tests)(void);
+ const percpu_tests test_funcs[NR_TESTS] = {
+ [PERCPU_VERIFY] = percpu_test_verify,
+ [PERCPU_STRESS] = percpu_test_stress,
+ [PERCPU_STRESSD] = percpu_test_stressd,
+ };
+
+ /* sanity checks */
+ if (percpu_alloc_max_size_shift > PAGE_SHIFT)
+ percpu_alloc_max_size_shift = PAGE_SHIFT;
+ if (percpu_test_num > NR_TESTS)
+ percpu_test_num = NR_TESTS;
+
+ pr_info("percpu_test: INIT, interval: %ld, max_shift: %d, run_tests: %s\n",
+ percpu_stressd_interval, percpu_alloc_max_size_shift,
+ percpu_test_num == NR_TESTS ? "run all tests" :
+ test_names[percpu_test_num]);
+
+ /* run a given test */
+ if (percpu_test_num < NR_TESTS) {
+ pr_info("TEST Starts: %s\n", test_names[percpu_test_num]);
+ ret = test_funcs[percpu_test_num]();
+ pr_info("TEST Completed: %s\n", test_names[percpu_test_num]);
+ goto out;
+ }
+
+ for (i = 0; i < NR_TESTS; i++) {
+ pr_info("TEST Starts: %s\n", test_names[i]);
+ test_funcs[i]();
+ pr_info("TEST Completed: %s\n", test_names[i]);
+ }
+out:
+ return ret;
}
static void __exit percpu_test_exit(void)
{
+ if (percpu_stressd_thread)
+ kthread_stop(percpu_stressd_thread);
+ pr_info("percpu_test: EXIT\n");
}
module_init(percpu_test_init)
--
2.31.1
On Mon, Aug 23, 2021 at 03:37:45PM +0530, Ritesh Harjani wrote:
> Make schedule_on_each_cpu as EXPORT_SYMBOL.
>
> Signed-off-by: Ritesh Harjani <[email protected]>
> ---
> kernel/workqueue.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> index f148eacda55a..6f15e4afbf38 100644
> --- a/kernel/workqueue.c
> +++ b/kernel/workqueue.c
> @@ -3309,6 +3309,7 @@ int schedule_on_each_cpu(work_func_t func)
> free_percpu(works);
> return 0;
> }
> +EXPORT_SYMBOL(schedule_on_each_cpu);
Please don't export random bits just for a test. Especially non without
an EXPORT_SYMBOL_GPL.
Hi Ritesh,
I love your patch! Perhaps something to improve:
[auto build test WARNING on dennis-percpu/for-next]
[also build test WARNING on wq/for-next linux/master linus/master v5.14-rc7 next-20210823]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Ritesh-Harjani/kernel-workqueue-Make-schedule_on_each_cpu-as-EXPORT_SYMBOL/20210823-180924
base: https://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu.git for-next
config: hexagon-randconfig-r024-20210822 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 79b55e5038324e61a3abf4e6a9a949c473edd858)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/a1287719d9dc710544e9968864a2069724b51427
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Ritesh-Harjani/kernel-workqueue-Make-schedule_on_each_cpu-as-EXPORT_SYMBOL/20210823-180924
git checkout a1287719d9dc710544e9968864a2069724b51427
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=hexagon
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
All warnings (new ones prefixed by >>):
>> lib/percpu_test.c:161:6: warning: no previous prototype for function 'percpu_test_verify_work' [-Wmissing-prototypes]
void percpu_test_verify_work(struct work_struct *work)
^
lib/percpu_test.c:161:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
void percpu_test_verify_work(struct work_struct *work)
^
static
1 warning generated.
vim +/percpu_test_verify_work +161 lib/percpu_test.c
160
> 161 void percpu_test_verify_work(struct work_struct *work)
162 {
163 percpu_test_verify();
164 }
165
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]
Hi Ritesh,
I love your patch! Perhaps something to improve:
[auto build test WARNING on dennis-percpu/for-next]
[also build test WARNING on wq/for-next linux/master linus/master v5.14-rc7 next-20210823]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Ritesh-Harjani/kernel-workqueue-Make-schedule_on_each_cpu-as-EXPORT_SYMBOL/20210823-180924
base: https://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu.git for-next
config: alpha-randconfig-r013-20210822 (attached as .config)
compiler: alpha-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/a1287719d9dc710544e9968864a2069724b51427
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Ritesh-Harjani/kernel-workqueue-Make-schedule_on_each_cpu-as-EXPORT_SYMBOL/20210823-180924
git checkout a1287719d9dc710544e9968864a2069724b51427
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=alpha
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
All warnings (new ones prefixed by >>):
>> lib/percpu_test.c:161:6: warning: no previous prototype for 'percpu_test_verify_work' [-Wmissing-prototypes]
161 | void percpu_test_verify_work(struct work_struct *work)
| ^~~~~~~~~~~~~~~~~~~~~~~
vim +/percpu_test_verify_work +161 lib/percpu_test.c
160
> 161 void percpu_test_verify_work(struct work_struct *work)
162 {
163 percpu_test_verify();
164 }
165
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]